Apparatus for treating evaporated milk



Dec. 18, 1945. R o so A 2,391,203

APPARATUS FOR TREATING EVAPORATED MILK Originai Filed March 3, 1941 4Sheets-Shet 1 v QMW v 41.55/77 K A/OMPJON Dec.18, 1945. A; R. THOMPSON2,391,203

APPARATUS FOR TREATING EVAPORATEDMILK Original Filed March {5, 1941 4Sheets-Sheet? 41.5fm" A. THOMPJON Dec. 18, 1945. THOMPSON 2,391,203

APPARATUS FOR TREATING EVAPORATED MILK Original Filed March :5, 1941 4Sheet-Sheet s \O. 53; QM? W Dec. 18, 1945. A. R. THOMPSON 1,

APPARATUS FOR TREATING EVAPORATED MILK Original Filed March 5, 1941 4She'ehs-Sheet 4 Ami/FM? TA/OMFJON Patented Dec. 18, 1945 UNITED STATEATPARATUS FOR TREATlhlG EVAPORATED MILK Albert R. Thompson, Los Gatos,Calii'., assignor s PATENT OFFICE to Food Machinery Corporation, SanJose, Calii'., a corporation of Delaware Original application March 3:1941, Serial No. 381,492. Divided and. this application June 26, 1944,Serial No. 542,079

- for Method and apparatus for treating evaporated milk.

One object of the presentinvention is to provide an improved apparatusfor processing milk.

Another object is to provide an apparatus for treating evaporated milkwhich employs a heat exchange chamber provided with a reciprocable and astationary canway portion wherein the cans are permitted to roll duringtheir travel through the reciprocable canway portion but are preventedfrom rolling during their travel through the stationary portion of thecanway.

Other and further objects and advantages of the present application willbecome apparent from the following description and drawings in which:Fig. 1 is a plan view showing somewhat diagrammatically the arrangementof the apparatus.

Fig; 2 is an end elevation of the feed end of the sterilizer.

Fig. 3 is an end elevation of the discharge end of the sterilizer andthe feed end of the cooler.

Fig. 4 is a vertical longitudinal section of the sterilizer with thereel removed and the canway 1 Claim. (01. 99-365) and accordingly thedetailed construction thereof hasnot been disclosed. The sterilizer B isan enclosed pressuretight chamber adapted to be supplied with a heatingmedium such as steam under pressure and maintained at the sterilizingtemperature. The cooler C is an enclosed pressuretight chamber adaptedto be supplied witha cooling medium such as water. The cooler is alsosupplied with compressed air from any suitable source so as to maintaina pressure above atmospheric therein.

The filled and sealed cans, as indicated at l9, are discharged from thefilling machine A and are received in rolling procession by an inclinedshown in elevation to illustrate its configuration.

" for sliding movement in the shell of the sterilizer.

Fig. 8 is a vertical transverse section through the feed end of thesterilizer.

Fig. 9 is a diagram illustrating the correlation of heat and agitationcontrol. I

Referring to Fig. 1, reference character A indicates a can filling andsoldering machine, B'a sterilizer and C a cooler. These units "arearranged so that the cans pass in procession from one to the other inthe order named. The can filling and soldering machine A is of thecontinuous automatic type adapted to receive a continuous file orprocession of cans and to fill them with evaporated milk through smallopenings provided in the head of each can, and then' to apply solderover the openings to hermetically seal the cans.

Machines of this type are well known in the art gravity chute 29. Thechute 29 delivers the cans to an elevator 2| which discharges them intothepockets 22 (Fig. 8) of a rotary pressuretight valve 23. The casing 25of the valve is mounted over an inlet 25 in the top of the sterilizer Bby means of a casting 21. As the valve rotates, the cans are introducedone after another into longitudinal can channels formed between rails 3|on a reel 32. The reel 32 is mounted on a shaft 33 which, as shown inFig. 4, is rotatably mounted in bearings 34, 35 in heads 36, 31respectively,

' which close the ends of the cylindrical shell 39.

A gear 38 is keyed to the end of shaft'33 for rotating the reel.

A canway'49 (Fig. 4) formed by helically trendingT rails 4|, is providedfor advancing the cans through the sterilizer along the can channels onthe reel, the base flanges 4m and ribs 4") of adjacent convolutions ofthe rails cooperating to form the canway in which the cans are advancedin rolling procession by the rails 3| and the reel 32. This canway isconstructed in two sections. The first section 42, which extends fromthe inlet 29 to an intermediate point in the sterilizer, is slidablymounted for longitudinal reciprocation, While the other section 43 isstationary, being rigidly secured to the shell 39. The movable andstationary sections 42, 43 together provide a continuous canway 49 toguide the cans through the sterilizer from the inlet 26 to the outlet44.

The movable section of the canway comprises a plurality of helical turnswhich are secured together as an integral unit by means of six parallelstraps 45 (Figs. 4 and-8). straps have sliding bearing on straps 46(Figs. 4 and 7) which are .welded to the shell 39. The canway also bearsagainst two spacer strips 41 which are welded to the shell. In thismanner the movable section 42 of the canway 49 is sup-. ported in theshell 39 for sliding movement back and forth parallel to the reel shaft33.

A ring 59 (Figs. 4 and 11) isrigidly connected The two lowermost to themovable canway unit 42 :by means of plates SI, 52, 53. Two pins 54 aremounted on the ring 50 and are connected by links 55 to levers 56splined on shafts 51. The shafts 51 extend laterally outside the shell30 in bearings 58 mounted on the shell. The outer ends of the shafts 51have levers 59 splined thereon. The

depending ends of the'levers 59 are connectedby means of pivot pins 60with links 6|, the opposite ends of which are 'pivotally attached bymeans of bearings. 82 (Figsr 2 and 4) with cranks 63 formed in atransversely extending shaft 64. The shaft 64 (Fig. 4) is supported forrotation in bearing brackets 65 mounted on the exterior of the shell,and has a pulley 66 thereon which is belt-driven from a motor 61,preferably through a variable speed drive 68, so that the speed ofrotation of shaft 64 can be varied somewhat if desired. It will beapparent that when the crank shaft 84 is rotated the levers 56 and 59will oscillate, causing reciprocation of themovable section 42 (Fig. 4)of the canway 40.

In order to facilitate introduction of the cans into the reciprocatingsection of the canway the inlet end of the canway which is disposedbeneath the sterilizer inlet 26 is formed by means of two rails 69 andHI (Fig. 4) which are T shaped in section. For a short distance adjacentthe terminus of these rails at the inlet 26 their inner base flanges arecut away at H and 12 (Fig. to admit the can .into' the channels betweenthe reel rails 3|. The rails 69 and are also spread apart for a shortdistance back from their ends I3, 14, the reason for this being that therail ends move from the full line position to the dot-dash line positionand return in each reciprocatory stroke of the movable part of thecanway. Hence the rail ends, I3, 14 must be spaced apart a distanceequal to the length of the can (shown in broken lines at I 9) plus thestroke of the canway and a small amount of clearance, so thatneither endwill obstruct admission of the can to the reel and canway.

In operation, the valve 23 (Fig. 4) is driven in timed relation with therotating reel 32 so as to deposit the cans between the ends 13, 14 (Fig.5) c of the canway and into the channels between the rails 3| (Fig. 8)of the reel which carries the cans into the canway: The rails 89, 10(Fig. 5) converge a short distance back from their inlet endterminus toreduce the spacing therebetween which was necessary to admit the can, sothat by the time the can has been carried to the point 16 in the canwaythe ribs of the rails 68, 10 engage the ends of the can and impartreciprocatory movement thereto.

The rails 69, 10 (Fig. 4) form substantially the first half turn of thehelical canway, and the pitch of thisinitial half turn is made reaterthan that of the rest of the canway in order to rapidly remove the canfrom the plane of the inlet 26, because the next turn must begin at 11beside the inlet. The rail 10 merges with the rail 69 at 18 and fromthis point on throughout the rest of the reciprocating canway section asingle rail is used, both sides of the rail rib over this part of thecanway being effective on the cans. The use of the single rail over thispart of the canway is made possible because the pitch of the helixremains constant.

As the cans travel around the section 42 of the canway, thereciprocation of the canway shakes them back and forth to vigorouslyagitate the milk. The rate of rotation of the reel 32 is such that bythe time the cans arrive at the end 19 of the reciprocating section ofthe canway the milk temperature has reached the maximum sterilizingtemperature and the can is ready to enter the stationary section 43 ofthe 5 canway.

The junction of the end 19 of the reciprckating section 42 of the canwaywith the beginning 80 of the stationary section is shown in detail inFigs. 4 and 6. It will be noted that the end 19 is forked to provide twoguiding flanges 8|, 82 which are alternately aligned with the rib 83 ofthe stationary canway rail 84 at each end of the stroke of the canwaysection 42. In the first turn of the stationary section 43 of the canwaythe pitch is increased to obtain sufficient clearance to permit thereciprocation of the last turn v of the reciprocating section 42 of thecanway. This necessitates the use of the double rail constructioncomprising the two angles 85, 88 which diverge at 81 and converge at 88.I

The can is transferred from the reciprocating section of the canway tothe stationary section in the following 'manner: As the can approachesthe end of the reciprocating section its right hand end is guided by themoving rib 8| onto the stationary rib 83. Throughout most of the firstcon volution of the stationary canway section the right hand end of thecan is guided by the rib of the rail 85. When the can again arrivesopposite the Junction the left hand end of can is guided by the movingrib 82 onto the stationary rib 83.

- In the next convolution the left hand end of the can is guided by'th'erib of the rail 86. When the left hand end of the can passes the point88 the can enters the stationary canway proper which is formed of asingle rail 89 coiled in a helix of constant pitch. Upon arrival at thepoint 90 double rails 91, 92 .are again employed to increase the pitchand shift the can over into line with the discharge outlet 44. i

It will be noted by reference to Fig. 8 that the rails 3| of the reel 32are of conventional T- shaped form at the inlet end of the reel, andthese rails are of this shape from the inlet end of the reel to theplane of the junction between the reciprocating and stationary sectionsof the camway 40 as indicated by the arrow 95 in Fig. 4.

In other words, the T-shaped form of the rails 3! extends throughout thelength of the reciprocating canway section 42, and by this constructionit will be observed (Fig. 8) that as the cans are advanced around theunder side of the reel they are free to engage with the base flanges 4laof the canway rail so that they are caused to roll thereon as they arepropelled by the reel rails 3|.

Thus during the travel of the cans through the reciprocating section ofthe canway 40 they receive maximum agitation since'they are not onlyvigorously shaken by reciprocations of the can- 0 way but are alsocaused to roll on their own axes along the lower portions of the canwayconvolutions.

The remainder of the reel, from the plane of the junction between thetwo canway sections as indicated at 95 in Fig. 4, to the discharge endof the reel, is of non-agitating construction such as disclosed in U. S.Patent No. 2,211,802, issued to me August 20, 1940, the ribs of therails 3| being provided with flanges 93 along their outer edges,

as best seen in Fig. 3, so that throughout the length of the stationarycanway section 43 the rails 3| are of I-shaped section. Thus the sectionof. the reel is of the non-agitating type, so

called because of the fact that the flanges 93 serve to support the cansas they are carried around the underside of the reel and therebymaintain them out of engagement with the base flanges la 01 the canway.Consequently agitation of the cans is minimized because they areprevented from having any rolling engagement with the canway such asthey do alone the reciprocating canway section, and are merely carriedaround bodily by the reel without any rolling motion. The only agitationimparted to the cans along the stationary section of the canwaytherefore is the very slight amount due to the turning of the cans withthe reel.

When the cans leave the sterilizer through the discharge outlet 44 theyare transferred to the cooler C (Fig. 3) by means of a pressure tighttransfer valve I which may be of the construction shown in U. S. LettersPatent No. 1,467,960, issued to me September 11, 1923. The cans are thenconveyed through the cooler by means of a conventional reel and canway,not shown, but which may be similar to the reel and canway illustratedin the above patent. Upon arrival. at the end of the cooler C (Fig. 1)the cans are removed therefrom through a pressure tight discharge valveI0 I.

The driving mechanism will now be described. A'motor I02 (Fig. 1)mounted on top of the sterilizer B has a belt arid pulley connection I03with the shaft I04. Pinions I05, I00 secured to the ends of the driveshaft I04 drive the gears 30, I08,- respectively, secured to thesterilizer reel shaft 33 through intermediate gears I 00 (Fig. 2), H0(Fig. 3). The gear I00 (Fig. 3) drives the gear III which operates thetransfer valve I00. The gear III meshes with the gear H2 secured to theshaft IIB of the cooler reel. The rotary pocketed valve which introducesthe cans into the sterilizer is driven by the gear I It (Fig.- 2)- fromthe gear 38, and the gear train I I5 provides a drive for the elevator 2I.

The operation of the apparatus is as follows:

' The cans are filled with evaporated milk and sealed in the machine A(Fig. 1). In rolling procession they descend the gravity chute 20 to theelevator 2| which deposits them into the valve 20 (Fig. 8) whichintroduces them one after another into the can channels formed by therails 3 I on the sterilizer reel.

The reel is rotating and carries the. cans into the reciprocating canwaysection 42 which begins to vigorously shake the cans. As the reelrotates, the .cans are free to roll on the canway because the canchannels are open in this part of the reel. The rolling and shaking ofthe cans provides maximum agitation which promotes the heat exchangetoraise the milk. temperature as rapidly-as possible, it beingunderstood that the interior of the sterilizer is maintained atsterilizing temperature, by the introduction ofsteam under pressurethereinto.

The rate of rotation of the reel is such that when the cans arrive atthe end of the reciprocating canway 42 (Fig. 4) the milk hassubstantially reached sterilizing temperature. The can's then pass intothe stationary portion 43 of the canway which results in discontinuationof the shaking. In addition, the flanged portion '93 (Fig. 3) of therails 3| which begins at this point serves to restrain the cans fromrolling on the canway. Thus, when the milk temperature reaches a maximumthe agitation is discontinued .and held to a minimum during the ensuingholdare then transferred by the valve I00 (Fig. 3) to the cooler wherethey are deposited in the rotating reel of the cooler. This reel ispreferably of the agitating type to provide at least moderate agitationto prevent the formation of skin as the milk cools. After being cooledthe cans are discharged from the cooler through the valv IM and thetreatment is finished.

The manner in which the, temperature and agitation are controlled isillustrated by the diagram in Fig. 9. The abscissas are units of timethe progress of the cans being from left to right in the direction ofthe arrow I30. The ordinates are degrees of temperature and agitation.The temperature curve is in full lines and the agitation curve in brokenlines. It is to be understood that these curves are not specifically toscale but were drawn merely to illustrate in a general way the time ofincrease and decrease in temperature and agitation as the milk istreated in the apparatus of the present invention.

The temperature of the milk as it leaves the filling machine and entersthe sterilizer is indicated at I3I. As the cans progress through thefore part of the sterilizer they receive maximum agitation indicated bythe brokenline I32 and the milk temperature rises to the sterilizingtemperature at I33. At this point the cans are transferred from themovable canway to the stationary canway and the agitation drops from amaximum at I38 to a minimum at I35.

The milk temperature remains at the sterilizing temperature as indicatedby the line I36 during the travel of the cans through the stationarypart of the sterilizer canway, during which time it receives minimumagitation as indicated by the broken line I31. During the travel of thecans through the cooler the milk temperature falls from I38 to I39. Thecan receives increased agitation in the cooler to aid th heat exchangeand prevent the formation of skin, as indicated by the broken line I00.

Having thus described my invention, what I claim as new and desire toprotect by U. S. Letters Patent is:

An apparatus for treating evaporated milk in cans comprising a heatexchange chamber having an inletand an outlet, a helical canway in saidchamber, a portion of said canway being reciprocable relative to saidchamber, the remainder of said canway being stationary relative to saidchamber, means to reciprocate said reciprocable portion of said canway,a rotary reel within said canway having longitudinal can channelsthereon, said can channels being open in said reciprocable portion ofsaid canway to permit the cans to roll on the canway, and means on saidcan channels in said stationary portion of said canway to restrain thecans from rollin on the canway.

ALBERT a. THOMPSON.

